Respirator.



, n. 1). BARNUM.

' RESPIRATOB.

APPLICATION FILED FEB. 26, 1904 1,000,706. Patented Aug.15,1911.

,WHZTESSGS I Tnuencor D- QQIMQM1 Dana D.Ec rr-num.

@WZWW' mouth and nose.

" UNITED STATES PATENT, OFFICE.

DANA n. IBABNUM, or WORCESTER, MASSACHUSETTSIASSIGNOR r PHINEAS L;RIDER,

or WORCESTER, MASSACHUSETTS.

zmsrnmron.

To all whom it may concern:

' Be it known that I, DANA D. BARNUM, a

of attachment to the band E. The cup is citizen of the United States,residing at Worcester, in the county of Worcester and Commonwealth ofMassachusetts, have invented a new and useful Improvement in,Respirators, of which the following is a specification, accompanied bydrawings forming a part of the same, in which- Figure 1 represents ahuman head show-' ing my improved respirator applied to the Fig. 2 is arear view of my improved respirator, and Fig. 3 is a central verticalsectional view of the same.

Similar reference letters and figures refer to similar parts in thedifferent views.

My present invention relates to a respirator or device for inclosing thenose and mouth, and having means for forcing air to the interior wherebya constant supply of fresh air is supplied for breathing.

My present invention is designed for the use of miners, gas men, andothers required to work in impure air or noxious vapors i and it enablesa constant supply of fresh air to be provided for breathing purposes andat a uniform pressure which is automatically controlled, and Iaccomplish this result by'means of the apparatus hereinafter describedand illustrated in the accompanying I drawings; the novel features of myinvention being pointed out in the annexed claims. v Referring to theaccompanying drawings A denotes a cup for the nose and mouth,

preferably made of flexible and semi-elastic material, such for example,as rubber, and of sufiicient diameter and depth to receive the chin andnose of the wearer and 40 inclosing the mouth and nostrils, with theedge B of the cup pressing against the face. The cup is provided with anotch C to receive the nose, and on the opposite and lower side the cuphas an interior projection D adapted to press against the under side ofthe chin and within the angle of the jaw bone, said projection fittingthe angular space included within the sides of the jaw bone, and therebyholding the cup from movement. The cup is drawn against the face by anysuitable means of attachment to the head of the wearer, preferably bymeans of an elastic band E, E, attached to the sides of the cup andpassing around the back of the head, and an elastic band FSpecificationbf Letters Patent;

Patented Aug. 15,1911.

Application filed February 26, 1904. Serial No. 195,399.

attached to the upper side of the cup and passing over the top of thehead to a'point thereby drawn closely against the face. The edge Bshould be formed of some elas tic material and is preferably chamfered,

as shown at G, Fig. 3, to enable the edge to qualities of the face; butin case the cup is made of rigid or unyielding material, it should beprovided with a yielding or elastic edge to accomplish the purposenamed.

From one side of the cupand communicating with the interior is a pi e -Htothe end of which may be attached a ose I leading to a pump or othersource of air supply, not shown, by which air is forced into theinterior of the cup A. It is desirable to supply a regular and constantflow of air to the cup which is inhaled and exhaled by the wearer, andas the pressure of air increases in the cup due to its constant supplyfrom the pump, the pressure of the edge B against the face is overcomeanda portion of the air contained in the cup escapes. In this way theair is kept pure within the cup as the exhaled air from the lungs of thewearer escapes between the edge of the cup and the face, and its placeis supplied by fresh air from the pump. I thus provide my respiratorwith a valvular margin which will yield under suflicient pressure andallow the air within the 'cup to escape and will immediately close whenthe pressure is relieved. I therefore obviate entirely thenecessity-ffor the use of a more or less complicated outlet valve. Ihave shown this valvular margin constructed of rubber or an elasticmaterial, but I do not confine myself to such form of construction v asany margin consisting of a yielding edge would come within my invention.

The amount ,of air pressure maintained within the cup A can be regulatedsufliciently for all practical purposes by increasingor diminishing thepressure of the edge B against the face which may be conveniently doneby varying the ten'sion of the bands E and F and to allow the tensionmatically regulate the pressure of air supplied to the wearer, but Ialso effect the desired change in the air s'ufliciently to prevent. itsbecoming too impure to be breathed.

My improved respirator is extremely simple and inexpensive and containsno movable parts, such as valves and the like which are liable to getout of order, and it can'be quickly applied to or removed from the face.

'lhe notch C inclosing the nose securely holds the cup from beingrotated on the face and the projection D adapted to enter the hollow ordepression behindthe jaw bone not only serves a similar purpose but italso prevents the lower edge of the cup from being pulled forward whichmight remove it from the face or destroy the close contact between theelastic edge B and the surface of the face, thereby allowing an undueescape of air from the cup. I

YVhat I claim as my invention and desire to secure by Letters-Patent is'1. A respirator, comprising a cup made of air tight material, means forattaching said cup to the head of the wearer, means for conducting airinto said cup, with the edge of said cup in contact with the face of thewearer sufficiently yielding to lift as the breath is exhaled andsufficiently elastic to close as the pressure within said cup decreases.

2. A respirator, comprising a cup made of airtight material, means forconducting air into said cup, means for attaching said cup to the headof the wearer with the edge in contact with the face, said edgesufficiently beveled to be the first to yield to increase of pressurewithin said cup and constructed of sufficiently elastic material toclose as the pressure within said cup de-- contact with the face, and anonyielding projection with said yielding edge arranged to engage theangle within the jaw bone of the wearer, thereby preventing forward orlateral displacementof said yielding edge.

Dated this 15th day of February 1904.

DANA D.' BARNUM.

Witnesses: i y A PENELOPE CoMBERBAoH, RUFUS B. FOWLER.

